This is a quick how-to for playing Thud online.
playing modes
The usual mode of play is that one side starts as the Dwarfs, the Battle is played, and then the sides are reversed and the reversed Battle is played. This is known as single play. Double play is when both battles are played at the same time, that is, the first player posts his first move as Dwarfs, the second player responds with a Troll Move and starts the return Battle with his (or her, of course) Dwarfs move.
Usually, these Battles have an unlimited number of moves each. The 'Quickfire' Thud option is where two players agree to a maximum number of moves for each battle, usually 30 moves each. This is known as the 30-moves option, but can also be the 24-move option or whatever you agree on.
posting moves
A move usually looks like
T D8 - C7 x C6 x B7 x B8
Or like
d C5 - C7 x C7
Or simply
d C5 - C7
These moves may be prepended with the move-number:
17: d C5 - C7
The move reads as follows: a 'd' or 'T' to indicate if you are moving a Dwarf or a Troll, then your move from starting coordinate to your end-coordinate., e.g. C5 - C7, followed optionally by thudding your opponents (zero, one or more, indicated by an 'x' followed by the coordinate where the Thuddee stood).
coordinate system
There is a Thud board coordinate map which you can find on
http://www.thudgame.com/images/boardmap.jpg.
Another, and I would argue easier 
, way to play is to use the ThudBoard application (see the ThudBoard section of the forum), which lets you copy and paste moves from the forum to the application and back. Quicklink for the ThudBoard application:
http://www.million.nl/thudboard/download.html
with more info to be found at http://www.million.nl/thudboard
finally
Sometimes somebody makes a mistake in moving the pieces on their board, and the boards of the two players now show different situations. This happens, and will be noticed, usually quickly, sometimes quite a bit later. If you think this is the case, just double-check with your opponent, and if this was indeed the case you can agree on restarting from a move where both boards were still in sync.
So to all: happy Thudding!
In my role as moderator I'd like to add this: unfinished games are a bore, not to mention a disappointment, to both the opponent who's been left dangling and any onlookers.
Please, if you aren't fairly sure you'll be able to finish a game, don't start one!
Please, if by any chance you'll be away for holidays or whatever, let your opponent know, preferably with an ultimatum ("I guess I'll be back by/after/in....").
Please, if any game you're playing turns out to be a real disaster, don't be ashamed to tell your opponent. We've all been there, we know how you feel. Just tell your opponent you've learned a lot from the game up till now, but you'd like to start over again knowing what you know now. Add some sugar and cream, and most likely your opponent will agree. Please don't just leave never to come back.
edit: Edited out the part in italics below because of the outcome of the discussion in here, and added bold type to the last sentence above.
I'd like to keep this place clean. I'm thinking of removing threads with unfinished games. Please do not reply on that topic in this thread (it's sticky and not intended for discussions), rather use the Ultimatum? poll, for any thoughts or feelings about this, or just for polling.
Happy Thudding!